Apnea rates in children with RSV bronchiolitis vary, according to new systematic review

The risk of apnea in children hospitalized with respiratory syncytial virus (RSV) bronchiolitis appears to vary widely, a new meta-analysis shows, and the risk may depend on certain confounding factors.

Dr. Vanessa Hill, a hospitalist physician at Christus Santa Rosa Children's Hospital in San Antonio, presented updated data on the rates of apnea in RSV bronchiolitis, a common occurrence with the condition. Using the Cochrane database, MEDLINE, and other sources, Dr. Hill and her team identified 564 abstracts. The 13 prospective and retrospective studies published from 1977 through 2007 that met the inclusion criteria included a total of 5,575 children who were hospitalized with RSV bronchiolitis. The apnea rates were stratified by gestational age: preterm (<38 weeks) or term (>=38 weeks).

Apnea rates varied from 1.2% (3 patients out of 257 patients; 95% CI, -0.13 to 2.53) in a 2001 study to 23.8% (44 patients out of 185 patients; 95% CI, 18.2-30.4) in a 1998 study.

Dr. Hill told VerusMed that the rates ranged so much because of the heterogeneity of the data.

"Unfortunately ... we can't do any statistical analysis because there's so much heterogeneity in the studies, particularly with authors including both term infants and premature infants and those who have comorbidities and coinfections," she said.

She stressed that many of the studies failed to report apnea rates by chronological age and failed to exclude children with underlying neurological impairment and/or coinfections.

"We really need to nail that [rate] down," she told VerusMed. "In order to do that, we need to do more of a prospective-type study where we eliminate confounders." She noted that there are other studies currently being conducted to address the variability in the rates.

In the current review, some of the studies give the impression that up to 20% of children hospitalized with RSV bronchiolitis would experience apnea, but Dr. Hill said that is not always the case. Furthermore, no controlled studies confirm RSV as an independent risk factor for apnea, she noted.

In clinical practice, Dr. Hill suggested, "I think you have to take it on a case-by-case basis."

She said the risk of apnea depends if you are treating a normal-term infant who is not compromised by any other comorbidity or a premature child. According to this review, apnea was most strongly linked with prematurity, young chronological age, and neurological impairment.